MCQ
Consider the shown system of two concentric thin metal shells. The inner hell has charge $Q$, while the outer shell is neutral. Potential difference between the shells is $V$. If the shell are joined by metal wire, then potential of the inner shell is
  • A
    $2V$
  • B
    $\frac{V}{2}$
  • $V$
  • D
    Zero

Answer

Correct option: C.
$V$
c
Before

$\mathrm{V}_{\text {outer }}=\frac{\mathrm{kQ}}{2 \mathrm{R}}$

$\mathrm{V}_{\text {inner }}=\frac{\mathrm{k} \mathrm{Q}}{\mathrm{R}}$

$\mathrm{V}_{\text {inner }}-\mathrm{V}_{\text {outer }}=\frac{\mathrm{kQ}}{2 \mathrm{R}}=\mathrm{V}$

After

$\mathrm{V}_{\text {inner }}=\mathrm{V}_{\text {outer }}=\frac{\mathrm{k} Q}{2 \mathrm{R}}=\mathrm{V}$

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